INFLUENZA VACCINATION AND PREGNANCY

Influenza or seasonal flu is cause by a virus, namely Influenza A or B.  To most healthy people, flu is an unpleasant experience characterized by symptoms of fever, muscle pain, nasal congestion and discharge.  It is usually a self-limiting disease and recovery is expected within a week.  Pregnant mothers, those with pre-existing medical condition, the very young and old population are prone to the more serious complications of influenza infection.  These complications include bronchitis, pneumonia, ear infection, sepsis, meningitis and encephalitis.

Influenza vaccine – risks and benefits

There is strong evidence that influenza vaccination for women who are pregnant is both efficacious and safe, with no increased incidence of miscarriages, fetal anomalies or neurodevelopmental disorders (Tamma 2009). There is also evidence that infants born to mothers vaccinated against influenza during pregnancy, compared with those not vaccinated, had lower rates of laboratory-confirmed influenza (4% versus 10%) and febrile respiratory illness (69% versus 97%) up to 24 months of age (Zaman K 2008).

The influenza vaccine can be safely taken at any stage of the pregnancy.  The injectable vaccine consists of inactivated virus (harmless as it does not contain live virus) and is not associated with adverse maternal or fetal outcome. The vaccine needs to be repeated annually due to the rapid viral mutation.  Its reported effectiveness is between 25-75%.

Despite the above benefits, the current vaccine uptake by pregnant mothers are low.  This is partly due to safety concern, poor patient awareness and lack of healthcare professional recommendation Koul 2014).

Conclusions

Pregnant women are at high risk of morbidity and mortality from influenza infection.  The current professional consensus strongly advocates influenza vaccine in pregnancy (ACOG 2014, RANZCOG 2014,WHO).

(Notes: At the time of writing, there is no known local guideline on influenza vaccine in pregnancy.)

 

References

ACOG committee Opinion 608. Influenza vaccination during pregnancy. Obstet Gynecol 2014

Koul PA et al., Poor uptake of influenza vaccination in pregnancy in northern India. Int J Obstet Gynecol 2014

RANZCOG. College statement: Influenza vaccine during pregnancy 2013.

Tamma PD et al., Safety of influenza vaccination during pregnancy. Am J Obstet Gynecol. 2009.

World Health Organization. Influenza (seasonal) fact sheet number 211.

Zaman K et al., Effectiveness of maternal influenza immunization in mothers and infants. NEJM 2008.

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DELIVERY AFTER MYOMECTOMY

Uterine fibroid is the commonest benign tumor of the uterus.  It can be associated with difficulty to conceive.  For those women who have uterine fibroid in pregnancy, it may cause pain due to degeneration, fetal malpresentation, or placenta previa. Most women with uterine fibroid may have undergone a myomectomy (surgical removal of the fibroid) prior to conception.  The scar from myomectomy surgery may be associated with the uterine wall weakness and increases the risk of uterine rupture.

How common is uterine rupture after a myomectomy?

Uterine rupture is an obstetrical emergency that can be catastrophic for the mother and fetus. Previous uterine surgery, including previous cesarean delivery or myomectomy, is an established risk factor, although the exact magnitude of the associated risk remains uncertain.

The consequences of uterine rupture affect both the mother and the fetus. Maternal consequences of uterine rupture include severe internal bleeding (hypovolaemic shock), genitourinary injury, potential need for hysterectomy, and maternal death. The fetal sequelae include fetal hypoxia and fetal or neonatal death. In 2003, Chauhan (2003) estimated that the overall rate of hysterectomy secondary to uterine rupture is 0.09% with a perinatal mortality rate of 0.04% and a maternal mortality rate of 0.02%.

 

The reported prevalence of uterine rupture following a Caesarean section is about 1%.  The frequency of uterine rupture is generally lower in developed countries compared undeveloped countries.  Meanwhile, the incidence of uterine rupture following myomectomy  is 0.79 %, which is comparable with that after cesarean section.

This risk is estimated to be lower than a classical Caesarean scar (incision on the muscular part of uterus).  The American College of Obstetricians and Gynecologists (ACOG) has cited a uterine rupture risk of 4%-9% for women with prior classical caesarean and a trial of vaginal delivery is contraindicated.

 

The current available evidence shows no significant difference between the incidences of a rupture during pregnancy following a laparoscopic (1.2 %) versus an open myomectomy (0.4 %).  The location, size of the fibroids and breach of the uterine cavity, surgical skills and technique (of suturing) also affect the likelihood of uterine rupture following previous myomectomy.

 

However, most studies on the safety of vaginal delivery after a myomectomy have several important limitations including non prospective, selection bias, under-reporting of iatrogenic complications and publication bias.  The under-estimated true risk of uterine rupture, a potentially life-threatening event is possibly contributed by more primary Caesarean section performed to avert medicolegal litigation.

 

Should women with myomectomy have trial of vaginal delivery?

 

The mode of delivery following myomectomy is controversial. Though the risk for uterine rupture is low (less than 1%) following a myomectomy, regardless of the technique used, the evidence is not robust.  It is clear that randomized studies are needed to study the effectiveness of laparoscopic myomectomy for the adverse outcome of uterine rupture before conclusive evidence can be used to present evidence-based recommendations for daily clinical practice.

 

This estimation of the incidence might be used for counseling women wishing to conceive after a myomectomy, but it should be done with utmost caution.

Some physicians will allow labor, as long as the uterine cavity has not been breached or less 50 percent of the uterine wall has been incised during myomectomy. However, ACOG currently recommends cesarean section following myomectomy be performed between 37 and 38 week to decrease the chance of the patient first going into labor with its risk of uterine rupture

Milton (2015) states that although there are limited data to support an elective Caesarean delivery, it should be offered to pregnant women who had myomectomies, in which large defects in the active segment of the uterus were created by removal of the fibroids. He feels that the total extent of the defect has a more significant impact on the risk of rupture compare to breach of the uterine cavity during the procedure.

There is currently insufficient evidence to determine the recommended mode of delivery following myomectomy. Some women are offered an elective Caesarean delivery by clinicians with the intention of reducing the risk of uterine rupture.

Conclusions

Uterine rupture during subsequent pregnancy seems to be a rare event.  Due to paucity of robust evidence and given the potentially devastating consequences of uterine rupture, a scheduled delivery at 38 weeks should be offered to women with myomectomy. However, this does not preclude a trial of vaginal delivery after an informed decision.

References

  1. ACOG Practice Bulletin, 2004.
  2. Bernardi TS et al., Archives of Gynecology & Obstetrics. 2014
  3. Chauhan SP et al., American J Obstet Gyne 2003.
  4. Milton, SH. In: eMedicine, ME Rivlin (ed). 2015

 

 

 

 

 

 

 

ADVANCED MATERNAL AGE AND PREGNANCY RISKS

There is currently an increasing trend towards delay childbearing across the world. Among the reasons are delay due to longer schooling, late marriage, shift in life priority, financial security, availability of contraception and women exercising their choices.  The consequence of this shift has led to more elderly pregnant mothers.

The commonly accepted definition of advanced maternal age (elderly) is 35 years or more. Studies have shown that pregnancy in this group of women is associated with a higher complication risk to both the mother and baby. Women should be supported in their decisions of whether to have children or not and when to plan childbearing. They should also be aware that the fertility and pregnancy outcomes change with age. For these reasons, women are encouraged to consider having families during the period of optimum fertility.

Pregnancy risks

Maternal age has been shown to affect pregnancy from conception to delivery. Biologically, the best period for pregnancy is between 20–35 years of age. The spontaneous conception rate is 75% in women aged 30 compared to 66% in those aged 35 years old (Leridon 2004). The pregnancy rate in elderly women is lower due to poorer egg quality associated with aging.  There is also a higher risk of spontaneous miscarriage. The reported miscarriage rate at 22 years old is 8.2%, but increases to 20% among women at 35 years of age.

Elderly mother has an increased risk of fetal chromosomal abnormalities and congenital anomalies. The risk of Down syndrome, the commonest cause of mental retardation is significantly increased from 1 in 1000 when the pregnant woman is 25 years of age compared to 1 in 250 at 35 years.

There is also a higher association of preterm birth, small for gestational age (small baby and intrauterine growth restriction, IUGR) among elderly mothers. The preterm delivery may be unexplained or iatrogenic, due to intervention following maternal complications (see below). Elderly mother may be associated with poorer placental perfusion or transplacental flux of nutrients. This led to an increased likelihood of a small for gestational age baby.  All these complications are associated with a higher neonatal intensive care unit admission and higher morbidity.

 

Increase perinatal morbidity and mortality

The risk of stillbirth (fetal demise after 28weeks gestation) is significantly higher in older women, partly due to the risks of aneuploidy (chromosomal anomalies) and fatal congenital anomalies.  The increased incidence of small for gestational age babies in the older women further contributes to the increased stillbirth rate.

 

Maternal complications

Older women are more likely to have pre-existing medical disorders such as diabetes mellitus or hypertension, which further complicate the pregnancy. There is an increased incidence of antepartum haemorrhage, malpresentation, pre-eclampsia and gestational diabetes mellitus.  All these complications lead to a higher operative vaginal delivery and Caesarean section.

 

Conclusions

Pregnant women aged ≥35 years are at increased risk of complications in pregnancy compared with younger women. Although women should be supported in their life choices, they should be aware of the possible problems that older mothers may encounter. Adherent to frequent antenatal visits, under an experienced obstetrician and increased fetal surveillance are some measures that may help to ensure a better outcome.

 

References

  1. Huang L et al., CMAJ 2008.
  2. Leridon H. Human Reproduction 2004
  3. RCOG statement on later maternity age 2009

 

VAGINAL SEEDING FOR CAESAREAN BABY!!

Vaginal seeding is a practice used for babies born by caesarean section that aims to mimic the exposure to bacteria that would have occurred during a normal vaginal delivery.  It involves rubbing vaginal fluid on the baby’s mouth, face and body, with the intention of exposing it to the “healthy” bacteria it would be exposed to in a vaginal birth.

This is not a standard practice.  It first hits the news in the United States in 2015.  It is believed that the practice of vaginal seeding improves the baby’s immunity.

The origin of this practice came from reports that found associations between being born by caesarean section and a “modest” increased risk of obesityasthma and autoimmune diseases. Other observational studies have shown associations between these conditions and changes in the different varieties of micro-organisms, such as bacteria normally present on and in the body.  These and other animal studies suggest exposure to these bacteria may play a role in developing a healthy immune system and reducing the risk of certain non-infectious diseases.

Despite the lack of studies proving cause and effect, many women in Australia and the UK are reportedly requesting the procedure after reading about it in the news.

Besides its unproven benefits, the vaginal seeding may risk the babies developing serious infections from potentially harmful bacteria (Group B Streptococcus, Chlamydia, Gonorrhea) or viruses (Hepatitis B, Genital herpes) from unaware mothers.

The current medical consensus is not to perform the procedure because there is no evidence of any benefits. The risk of harm cannot be justified. However, if the mothers have made an informed decision for vaginal seeding, their wishes should be respected.

Finally, the practice of breastfeeding and limiting exposure to antibiotics are both recommended ways to help the child obtain a wide variety of normal bacteria needed to build a strong immune system.  In summary, the practice of vaginal seeding lacks evidence to be routinely instituted on Caesarean birth babies.

VEGETARIAN DIETS AND PREGNANCY?

Vegan and vegetarian diets are plant-based diets. They are gaining popularity as people try to make better choices in terms of their health when it comes to food.  A vegetarian diet refers to diet that is devoid of animal (meat). It can be a total (vegan) or partial exclusion of animal derived food, allowing dairy products and eggs.

Plants, in general tend to be more nutrient-dense and associated with a number of health benefits, including lower body mass index, cardiovascular diseases, obesity, diabetes and cancer prevention. This diet also has a higher content of magnesium, folate, and fiber, compared to the meatier westernized diets.

Studies has demonstrated that partial vegan diet intake fulfilled the UK recommended nutritional intake (RNI) but the vegan had a lower vitamin B12, riboflavin, calcium and iodine.  These vegans were also had a lower iron, zinc and vitamin D due to exclusion of meat from their diet (Draper 1993, Philips 2005).

Effect of vegetarian diet in pregnancy

Draper (1993) finds that in non-pregnant vegetarians, the mean intakes of micronutrients met the UK recommended nutrient intake (RNI) among partial vegetarian but strict vegans have intakes of riboflavin, vitamin B12, calcium and iodine that were below the RNI.

Pregnancy is associated with an increased requirement for energy, protein and some micronutrients, including thiamin, riboflavin, folate and vitamins A, C and D. Although a vegetarian diet can meet the increased demand for energy and protein during pregnancy, but there may be difficult to achieve the recommended intake of some vitamins and minerals, especially for vegans, due to dietary restrictions. This group has difficulty meeting their requirements for riboflavin, vitamin B12, calcium, iron and zinc. The intake of these important nutrients during pregnancy need to be supplemented (Philips 2005).

Effect on pregnancy outcome

Studies comparing birth outcomes (e.g. birthweight, length of gestation) in vegetarian  mothers and omnivores, have so far not produced consistent results. One study found no difference in length of gestation, birthweight, birth length or head circumference between the babies of vegetarians, fish-eaters and meat-eaters (Drake 1998). Others found that white, vegan mothers had lower birthweight babies compared with women from the rest of the population (Sanders 1995, Reddy 1994).

 

Conclusions

The current evidence on vegan–vegetarian diets in pregnancy is mixed and limited. The type of dietary advice that is applicable to vegetarians and vegans during pregnancy depends, to a certain extent, on the type of vegetarian diet followed.  The vegetarian diet is associated with risk for low intakes of certain nutrients during pregnancy.

The vegetarian diets may be considered safe in pregnancy as most should be able to meet their nutrient requirements with careful dietary planning. However, those on very restricted diets may also need to consume fortified foods or supplements.

 

References

  1. Drake R et al., Vegetarian Nutrition: An International Journal 1995
  2. Draper A et al., British Journal of Nutrition 1993.
  3. Philips F. Nutrition Bulletin 2005
  4. Reddy S et al., European Journal of Clinical Nutrition 1994.
  5. Sanders TAB.  Pediatric Nutrition 1995

THE LATEST SCARE – ZIKA VIRUS AND PREGNANCY

For the last two months, the world is shocked by news of microcephalic babies born after suspected Zika virus infected mothers in South America. These babies have smaller than normal head circumference, with high probability of brain damage, blindness or even deafness. It affects more than 2000 pregnant mothers in South America and the government has advised women to postpone pregnancy for six to eight months in order to avoid potential infection.

Zika virus, is a member of the family Flaviviridae, together with dengue and chikungunya viruses. The main transmission is via mosquito bites, mainly the Aedes Aegypti and A. Albopictus. Majority of patient infected with Zika virus are asymptomatic while others presented with mild rash, fever, muscle pain and conjunctivitis. All these symptoms last for about one week. Only a few cases need hospitalization while Gullain- Barrre syndrome has been associated with this infection.

Testing of Zika virus infection in symptomatic pregnant mother can done using immunoglobulin M and neutralizing antibody. When congenital infection is suspected, an amniocentesis can be used to look for Zika virus RT-PCR.

Currently, there is no specific antiviral treatment available for Zika virus disease. The current treatment is generally supportive, including hydration, analgesia and anti-pyrexia.

 Recommendation for pregnant mothers

The CDC recommends that all pregnant mothers should consider avoiding areas where Zika virus transmission is ongoing. For those who have to travel to these endemic areas, a strict adherence to prevention from mosquito bite must be followed. This includes wearing long sleeved shirts and long pants, using insect repellent and staying in screened-in or air-conditioned rooms.

The viremia period for Zika infection is about one week. This virus will have been removed from the body’s circulation after this short period. Any pregnancy after this interval is unlikely to be harmed by Zika virus.

PELVIC FLOOR INJURY – A PRICE TO PAY FOR VAGINAL BIRTH?

Pelvic floor (Levator ani) injury occurs in 3 of 10 vaginal deliveries and often results in pelvic floor dysfunction including pelvic organ prolapse and incontinence.

The pelvic floor muscles is consist of three main muscle groups: the puborectal, the pubococcygeal, and the iliococcygeal. The main function is to support the vagina and pelvic organs, and maintenance of urinary and fecal continence.

During vaginal childbirth, the opening of the genital hiatus distends substantially to allow the passage of the fetus. This stretches the pelvic floor muscle greater than 3 times their original length, thereby putting strain on the muscles and can result in damage.

In addition, during the second stage of labor as the fetal head descends, excess stretch and distention of the muscles result in stretch and distention of the nerve to the levator ani. Prolonged stretching of this motor nerve has the potential to permanently damage the nerve, leading to laxity or sagging of one or both sides of the Iliococcygeus muscle.

 The above two labor related mechanisms have the potential to cause significant injury to the pevic floor muscle attachments and nerve supply, leading to an increase risk of urinary and fecal incontinence and future development of pelvic organ prolapse (POP).

 The prevention for pelvic floor dysfunction may be reduced by pelvic floor education and exercises during and after pregnancy. In one study, women who received pelvic floor therapy from 20 weeks’ gestation were less likely to report urinary incontinence in late pregnancy, at 3 months and 6 months postpartum. It appears that routine pelvic floor education or referral to pelvic floor physical therapy during the intrapartum and postpartum period may be beneficial, especially in high-risk patients.

 

Reference

  1. Dietz HP. Pelvic Floor trauma in childbirth. Aust N Z J Obstet Gynaecol. 2013;53:220-230.
  2.  Dietz HP, Lanzarone V. Levator trauma after vaginal delivery. Obstet Gynecol. 2005;106:707–712.