Does having one child mean no fertility issues? Here’s why secondary infertility can still happen

Having one child is often assumed to settle the fertility question. If conception happened once, many couples believe it will happen again. This assumption is also common among family members and can even delay timely medical evaluation. However, secondary infertility, which refers to difficulty conceiving or carrying a pregnancy after at least one previous pregnancy or birth, is more common than many couples realise. In several cases, the reasons are not linked to the first pregnancy.

Secondary infertility is an important but under-discussed concern in India. A systematic review and meta-analysis published in Reproductive Health in 2026, covering Indian studies from 1997 to 2023, estimated the prevalence of secondary infertility among women of reproductive age at 2%. Secondary analyses of National Family Health Survey data have also shown a rise in secondary infertility in India, from 19.5% in 1992-93 to 28.6% in 2015-16. These figures point to a clear need for greater awareness, earlier evaluation and more open conversations around fertility after the first child.

What are the main causes of secondary infertility?

The causes of secondary infertility are often different from those seen in primary infertility. They may develop or worsen in the years between pregnancies. Age is one of the most commonly underestimated factors. Ovarian reserve declines progressively after the early thirties, and the gap between the first and second attempts to conceive can be clinically significant. A couple who conceived without difficulty at 28 may face a different fertility picture at 34.

Can uterine scarring cause infertility?

Complications from a previous delivery can also affect future fertility. Uterine scarring following a caesarean section, pelvic infections after delivery or miscarriage, and changes in the uterine lining can all affect implantation. Asherman’s syndrome, where adhesions form inside the uterine cavity, may occur after uterine procedures or infections and may not always produce obvious symptoms.

Can PMOS affect fertility?

Hormonal conditions such as thyroid dysfunction and PMOS (earlier known as PCOS) can also emerge or worsen after a first birth. Male factor infertility is another important and often under-investigated reason. The assumption that a man’s fertility is already proven because he has fathered a child can delay semen analysis and couple evaluation. Sperm quality can change with age, weight gain, lifestyle factors, stress and chronic health conditions.

Secondary infertility can carry a distinct emotional burden. Because the couple already has a child, their difficulty in conceiving again is often dismissed or minimised. This can make it harder to discuss the experience and to seek timely care. Couples may wait for years before considering a fertility evaluation, simply because they believe previous conception rules out a current fertility concern.

At what age should a woman be tested for fertility?

A fertility assessment is recommended after 12 months of trying without success if the woman is below 35, and after 6 months if she is 35 or above. The purpose is not to create alarm, but to understand what may have changed. With the right evaluation, doctors can assess ovarian reserve, ovulation, uterine health, fallopian tubes, semen parameters and hormonal factors, and then guide the couple on the next appropriate step.