Secondary Infertility

Secondary infertility is the inability of a couple to conceive again after a previous pregnancy. The diagnosis applies after 12 months of regular intercourse without contraception. For women 35 or older, the threshold is 6 months. The earlier pregnancy counts regardless of how it ended. Secondary infertility is common. In one group of 370 couples receiving RRM care for infertility, 27% had already had a live birth.¹ Too often, couples receive false reassurance: a previous birth means nothing is wrong.

New problems can arise after a first pregnancy. A cesarean delivery leaves a scar on the uterus. A small pouch can form in that scar (an isthmocele). The pouch can make it harder for a new pregnancy to implant. One study followed 22 women whose infertility was linked to this scar defect. After repair surgery through a small scope, 14 of them (64%) conceived.² A surgical delivery can also cause scar tissue inside the uterus. Retained tissue after birth can do the same. This intrauterine scarring points to Asherman's syndrome. The thyroid gland can become inflamed after birth (postpartum thyroiditis). This inflammation can leave lasting hypothyroidism, an underactive thyroid. The condition can go unnoticed until a couple has difficulty conceiving. Endometriosis can begin or worsen between pregnancies. The male partner can change as well. A varicocele (a swollen vein in the scrotum), illness, and hormonal changes can all alter sperm over time.

RRM approaches secondary infertility as a new question rather than a repeat of the old one. Test results from the first pregnancy may no longer apply. Reassurance alone can delay the workup that finds what changed. The couple trying to conceive today may have a different problem from the couple who conceived two years ago.

The infertility is real. The search for its cause should be equally serious.