Factors Affecting Fertility

What affects fertility?


For most people, the instinct to start a family is the most natural thing in the world. So, when couples trying for a child run into problems, they can become anxious and even confused over what their next course of action should be.


As a simple rule-of-thumb, the need to seek medical attention for fertility hinges on these factors:


1. The age of the woman


The single most important factor that affects a woman's fertility is her age (Figure 1). Fertility is fairly stable until the age of 35 years, after which there is a gradual decline. From about 40 years of age, the drop in fertility is profound. It is therefore important that women who are reaching 35 and have not been able to become pregnant seek medical attention soon. This becomes urgent for women who are nearing 40 years of age.



2. The length of time trying to conceive

Once you decide to have a baby, it is easy to become concerned if you do not conceive within the first month of trying. But the fact is, even a normal, healthy woman (below the age of 30) who is regularly having intercourse only has a 20- to 40-per-cent chance of getting pregnant during any given cycle. So, what has gone “wrong” the other 60 to 80 per cent of the time? In most cases there is no medical reason – the cause is usually because the quality of the egg or sperm is insufficient to achieve fertilisation, or that fertilisation occurs but the embryo does not survive beyond a few days. In fact, the odds of conception are actually quite good once you look at them over the span of a year of trying, according to data from the National Center for Health Statistics in USA (Figure 2). 


Your Age Your chance of conceiving within one year

Under 25 96%

25 – 34 86%

35 – 44 78%


3. Medical problems

Do not delay seeking medical help, as your age is of crucial importance in determining fertility. The following points will help you to decide when you should seek urgent medical advice:


1. Your age is more than 35 years

2. You have been infertile for more than two years

3. You experience irregular periods

4. You or your partner have sexual problems

5. You have had previous abdominal operations

6. You have been on more than six cycles of ovulation induction medication

7. You have had more than four cycles of SO-AI (Superovulation-Artificial Insemination)


In the absence of any medical problems, women below the age of 30 should see a gynaecologist if they have trouble conceiving after one to two years of unprotected intercourse. However, those between 30 and 35 should seek attention after six to nine months. The urgency increases in women between 35 and 40 if they are not pregnant after six months; while women over 40 should seek medical attention after three months of unsuccessful trying.


In most instances, your gynaecologist should be able to perform a preliminary fertility regime and treat most of the problems, if any. If you have not conceived under your doctor’s care within six to 12 months, see a fertility specialist [also called an RE (Reproductive Endocrine) specialist, who is a gynaecologist with additional experience in fertility management], who can guide you through the wide range of available treatments.


It is important to understand the thinking process of your doctors so a decision that is correct for you can be made. This means that YOU actively participate in your treatment and assist your RE specialist in formulating the best possible plan to becoming pregnant.