Some couples who conceived easily when they started a family, find it more difficult when they want number two. Dr Gillian Lockwood of Midland Fertility Services looks at what you can do

Around 20% of couples suffer with what’s called ‘secondary infertility’, so you’re not alone, but it’s hard to accept and initially a lot of people ask ‘Why?’ or ‘What have we done wrong?’ There are no straightforward answers, just numerous possibilities and in order to get a second pregnancy going, quite complex investigations and treatment may be needed. Your first port of call should be your GP and you may then be referred to a fertility clinic.

Factors which cause secondary infertility

Age. For women in their late 30s and early 40s the chance of conceiving is actually quite low. See Fertile when you’re forty?

Fallopian tube damage. Complications during a previous pregnancy or delivery, or a recent pelvic infection, can harm or block the fallopian tubes and reduce the chances of eggs being fertilised.

Polycystic ovaries. This is a relatively common condition affecting women who have put on a significant amount of weight during their first pregnancy, increasing their body mass index above the normal range. This can interfere with regular ovulation, cause an imbalance of hormones and significantly reduce fertility. Unless women diet back down to the weight they were when they first conceived, they will not regain their previous fertility. Recent research shows that even a little weight loss will help improve your chances of conceiving.

Sperm count. Most healthy men retain their fertility well into middle-age but any chronic illness (like diabetes or high blood pressure) can have a detrimental effect not only on the sperm count but also on the mobility and structure of the sperm, both of which have a role to play in the fertility process.

There are occasions when, despite all the tests and investigations, no apparent cause can be found for secondary infertility. This is frustrating and upsetting, so after a year of trying (sooner if you’re mid-to-late 30s) you should consider active fertility treatment. Investigations can take up to two years to complete via the NHS. If you want to fast track, then see what your local fertility unit offers. Some offer an investigation package (which can cost around £100) providing results within four to six weeks.

Treatments
Irregular ovulation. Ovulation can be induced with fertility tablets such as clomiphene citrate or injections with gonadotrophins (fertility drugs) to restore regular, predictable ovulation.

Damage to the fallopian tubes. Surgery may be needed, or In-Vitro Fertilisation. See IVF: what you need to know. The woman is given hormones to stimulate the ovaries to produce a large number of follicles. The follicles are emptied and the eggs collected with ultrasound guidance. The eggs can then be fertilised with the partner’s sperm and the resulting embryos are transferred into the uterus two to three days later where, with luck, they will implant. A maximum of two to three embryos are transferred during a ‘fresh’ embryo transfer cycle, but any surplus embryos of good quality may be frozen for a subsequent attempt.

Sperm problems. Intrauterine Insemination (IUI) can help conception. A sperm sample is taken and prepared so that good quality sperm are retrieved. The insemination is carried out at the optimum time in the partner’s ovulation cycle. This treatment can be made more effective by gently stimulating the ovaries with hormones to ensure the woman releases two or three eggs with each ovulation.

If the sperm count is very low or if only a few eggs can be retrieved at IVF, then the technique of Intra-cytoplasmic Sperm Injection (ICSI) can be used. With this treatment the woman will undergo a conventional IVF cycle but once the eggs have been collected, one sperm is injected directly into each egg to fertilise it.

Even after a vasectomy or failed reversal, when a man will obviously not be able to ejaculate sperm because the vas deferens has been blocked, it is still possible to collect the sperm. This can be done surgically, either by taking them from the epididymis, or directly from the testes. The sperm can then be used with ICSI in an IVF cycle.

Overall, the chances of conceiving for a couple with secondary infertility are quite good. The key thing is to consider assisted conception techniques sooner rather than later. Don’t hang around hoping and waiting.