Subfertility to conceive is defined as failure to conceive  after 12 months of unprotected sexual intercourse.   The incident is estimated at 15% i.e one in seven married couples.  This number could be higher.

A healthy couple with regular sexual intercourse (at least three times /week) has a fecundity rate of 30%.  By the end of 1year, the pregnancy rate is about 80%.  Thereafter the pregnancy rate improved by only 10% the following 12months (see diagram 1).

Based on the above information, couple should be investigated after one year.

Steps towards conception

For conception to occur, the following factors must be in place.  This includes

1.  Adequate sperm count in the male partner

2.  Presence of ovulation

3.  Patent fallopian tubes in the female.

4.  Right timing of intercourse i.e ovulation period

In a woman with regular menstrual cycle, ovulation occurs 14 days prior to her menses.  When sexual intercourse occurs during this ‘fertile period’, possibility of pregnancy is high.  The motile sperm deposited in the vagina swims up through the cervical canal into the uterine cavity and fallopian tube.  It is at the fallopian tube where the egg (ovum) is fertilized.  Once fertilization occurs, the embryo travels down to the uterine cavity for implantation.  The fetus grows in the uterine cavity.

Common causes (Table 1)

1.  Semen abnormalities

Semen abnormality can occur in terms of quantity (low concentration) or quality (defective sperms).  Please refer to table 2

2.  Fallopian tube obstruction

Certain pelvic diseases such as pelvic inflammatory disease or endometriosis can cause adhesion to the fallopian tube, leading to obstruction.

3.  Absence of ovulation (anovulation)

Woman with regular menstruation is more likely to ovulate.  Polycystic ovarian disease is the commonest cause for anovulation.

Investigation for infertility (see table 3.)

The male and female factor contributed equally to the cause of subfertility.  However, there maybe normal investigation results in about 10-15% of cases.  The common causes of infertility are listed in Table 1. A serum day 21 Progesterone would be adequate to assess ovulation if the woman has regular menstrual cycle.  However, in the presence of irregular menses, other causes of anovulation should be investigated (see table below).

Semen analysis should be performed first to exclude male cause  of  infertility.  The sample is best collected after an abstinence of at least two but not more than five days.  Interpretation of this test must be in accordance to the WHO criteria and a second test performed if any abnormal result detected.

Hysteroscopy is usually preferred over laparoscopy to exclude tubal obstruction.  However, referral to a gynecologist for a diagnostic laparoscopy maybe indicated when there is suspicion of  endometriosis or pelvic infection.

Treatment option

All couple with difficulty to conceive need to be investigated and a decision         is then made on the level of care needed.   Couple should also be educated on timing of coitus  (‘fertile period’).  This can be determined by follicle tracking by ultrasound, urine LH test or demonstration of ‘spinbarkeit’ on cervical mucous.  The use of basal body temperature (BBT) is obsolete. In anovulatory cycles, the primary cause should be investigated and appropriate treatment given.

Early referral to gynecologist for IUI or IVF-ICSI is appropriate if the male partner has abnormal semen analysis.  Similarly, tubal obstruction should be further managed by the specialist.

Gynecologist trained in this field should further investigate women who failed to conceive after 6 cycles of clomiphene treatment.  Treatment options available at this level include ovulation stimulation and follicle tracking,  intrauterine insemination and assisted reproductive technique (IVF).

Table 1.  Common causes of  infertility




Male factor Inadequate sperm countPoor sperm quality
Female factor AnovulationTubal factor




Table 2.  Infertility investigation

Relevant history  Investigation

Poor sperm

Past history of mumps orchitis

Semen analysis

No ovulation

History of galactorrhea

Irregular menses



D 21 Se Progesterone

Se Prolactin

Thyroid function test

Pelvic ultrasound

Tubal obstruction

Suspected pelvic infection, endometriosis


Diagnostic laparoscopy

Unexplained All  examination & investigations normal

WHO criteria for semen analysis


>20 million/ml


>50% motile




> 50%