Fertility research indicates that the ideal age for a woman to have a child is in her early 20s. In Ireland now, the average age a woman has her first child is 31. Twenty years ago it was 26. So, why are we having babies at an older age, and should we change how we plan our families?
There are several reasons that explain why Irish women are starting families when they are older. The economic climate in Ireland means that women and couples have had to think long and hard about when to start a family. A woman who might have once thought of leaving the workforce to have a child might have to think twice about the financial consequences. Couples might need two full-time incomes to service their mortgage and other expenses.
Maternity benefit is at the discretion of Irish employers, and State benefit may not be sufficient for women in straitened financial circumstances.
There's also the enormous financial burden of full-time childcare to consider when the woman returns to work; many mothers end up taking part-time employment.
Undoubtedly the attitudes and atmospheres of some workplaces have a bearing on the decision to have children. Many women are aware of an unspoken negative bias within the workplace towards maternity leave, and the perceived disruption it causes in the work environment. So they strive to reach a position of seniority and relative safety before becoming pregnant.
And relationships have changed. People take longer to find their life partner. And then there's reliable long-term contraception that has enabled women to control their fertility.
The decision
when to have a child is not just confined to the first baby either. Couples can reach the stage where they ask themselves whether they can have a second or a third child. Sometimes it ends up being too late.
The idea of putting your life on hold for whatever reason is a major factor in the trend of older women having children and, consequently, the increasing rate of infertility in Irish couples.
What most women don't realise is that while they're climbing the corporate ladder, the quality of the eggs produced by their ovaries is declining. This becomes more marked over the age of 35, and egg quality is significantly reduced by the age of 40. What this means is that as you get older, your fertility reduces, and there's an increased risk of miscarriage.
One of the major factors contributing to the infertility rate of one in seven Irish couples is leaving pregnancy until an older age. Women should be more aware of the risks attached.
So, what can we do?
The Anti Mullerian Hormone (AMH) blood test was specifically formulated to allow women to defer pregnancy for up to two years at a time, by measuring their egg quality or ovarian reserve. This gives a very accurate idea of whether your fertility is sufficiently robust that you
can defer pregnancy for a few years or whether you should be seriously considering pregnancy sooner due to a low result. This test is of very little relevance to women over 40 as deferring pregnancy is never recommended. It's also used increasingly to predict the success of fertility treatments for women embarking on IVF.
The question is, do you put off having a baby until a recession is over, until you have fulfilled your ambitions at work or traveled the world? Or do you prioritise fertility ahead of lifestyle choices?
There's no doubting the physical evidence that we should be having children at a much younger age, but we live in a changing world. Women are increasingly prominent in the workplace, with society organised around full-time employment and smaller families.
Women today are making different choices to those from previous generations, but they also need to understand the possible consequences of those choices on their hopes for a family.
Dr Rachel Mackey is a women's health specialist at Women's Health Clinic in Dun Laoghaire and author of The Women's Health Book: A Guide for the Irish Woman. She offers her expertise on a wide range of health issues, using extensive obstetric and gynaecological expertise. 
