什么时候生孩子比较好？

Over the past three decades, there has been a steady increase in the average age of parents. Advances in fertility science mean that people can, literally, put their eggs or sperm on ice and delay the start of parenthood.

过去三十年里，新生儿父母的平均年龄始终在增长。生育科学的进步意味着人们可以从字面上将他们的卵子或精子冷藏起来保存很久，直到他们想要一个孩子。

Many large companies, such as Apple, Facebook and Google, now offer egg freezing to employees as part of their healthcare package. Putting off having a baby has never been easier or more socially acceptable. But is it a good thing?

许多大公司，如苹果、Facebook和谷歌，冷藏精子或卵子的服务项目已经成为了员工医疗保险的一部分。历史上，我们从来没有机会像现在一样随心所欲地决定自己的生育时间，人们也从来像现在一样将推迟生育视为平常。但这是好事吗?

There are three things to consider. Will your child be healthy? Will you get pregnant? How much will it cost?

有3件事需要考虑。经由延迟生育手段得到的孩子健康吗?能够成功妊娠吗?它要花多少钱?

Parents have a moral obligation to give their child the best start in life.

父母有道德和义务为孩子提供最好的人生起点。

But children born to mothers over the age of 35 and fathers over the age of 45 are at greater risk of having genetic and neurodevelopmental disorders, such as schizophrenia and autism, which arguably affects the child's quality of life.

但是，35岁以上的母亲和45岁以上的父亲的孩子患遗传和神经发育障碍的风险更高，例如精神分裂症和孤独症，这可能会影响孩子未来的人生。

Also, older parents are more likely to need assisted reproduction, such as IVF, which is associated with babies being born early or with low birth weight. Babies born via IVF are also at higher risk of cardiovascular and metabolic disease in later life.

此外，年龄较大的父母更可能需要辅助生殖技术，例如IVF，有研究发现，其中存在着未知的风险。通过体外受精(IVF)出生的婴儿在以后的生活中也有较高的心血管和代谢疾病风险。

If prospective parents freeze their eggs or sperm when they are younger, they can reduce some age-associated risks but not those due to IVF.

如果准父母在他们年轻时就冻结了他们的卵子或精子，他们可以减少与年龄相关的风险，但不会降低因IVF导致的风险。

The method of fertilisation in IVF with frozen eggs is intracytoplasmic sperm injection (ICSI), where sperm is injected into the egg. ICSI can also increase the risk of birth defects in children.

为冷冻卵子受精的方法叫做卵胞浆内单精子注射(ICSI)，就是将精子物理注入卵子。 ICSI可能还会提高儿童出生缺陷的风险。

Using ICSI is also more common in older men where sperm motility is poor. Again, not the best start in life.

在精子活性低的老年男性中使用ICSI更为常见。所以又回到了最开始所说的高龄父亲的问题。

So you've decided to wait

不急着怀孕

If you want to wait to have children, you are not alone.

如果你这么想，那你并不孤单。

Most couples will fall pregnant after trying for a year. Although one in sevencouples has trouble conceiving – and age is a big player in this.

大多数夫妇会在决定要孩子一年后怀孕。虽然有七分之一的夫妇在怀孕方面会遇到困难——年龄是一个重要的指标。

One in six women aged between 35 and 39 years of age will not conceive after one year. If their partner is over 40, this drops to more than one in four.

年龄在35至39岁之间的女性不会在一年内受孕。如果他们的伴侣超过40岁，那么这一比例将下降到四分之一。

IVF is seen by many as a fail-safe way of conceiving, but its success is also governed by age. For a woman using her own eggs, the success of IVF over 40 is less than 10 percent.

IVF被许多人视为保险的兜底手段，但其成功也受年龄的制约。对使用自己卵子的女性来说，年纪超过40的女性，IVF的成功率不到10%。

The risks of delaying parenthood have been simulated with computer modelling.

计算机建模模拟了大龄父母的风险。

If a 30-year-old woman delays trying for a baby from age 30 until 35, her chances of falling pregnant are reduced by 9 percent, but IVF will only compensate for 4 percent.

如果一名30岁的女性在30岁至35岁之间推迟了生育的尝试，她以后怀孕的几率会降低至9%，而IVF只能在此基础上提高4%。

And if you want to freeze eggs, great. Except women produce fewer eggs ("oocytes") as they get older, so older women may need more rounds of stimulation to store the eight to ten eggs needed for a reasonable chance of a successful birth – and this can be extremely expensive.

如果你想冷冻卵子，那很好。女性随着年龄的增长，排卵(“卵母细胞”)减少，老年妇女可能需要更多的干预才能储存成功分娩所需的8到10个卵子——这一过程代价不菲。

What will it cost you?

生育开销

Although IVF is expensive, there are also other significant indirect costs of having a child.

虽然IVF的价格就已然十分昂贵，但生孩子还有其他不容小觑的间接开销。

The "motherhood wage penalty" is often cited in economic discussions about the effect of motherhood on women's careers. It is the loss of earnings women are subjected to as they move into a non-paid job for a period of time.

比如，关于女性职业生涯的经济讨论中经常引用的“孕妇隐形工资惩罚”。它等价于女性因在一段时间内无法工作而损失的收入。

There is some evidence to suggest that women can earn more by delaying motherhood from their early twenties to early thirties.

有数据表明，如果女性在二十的时候将生育推迟到三十岁后，可以赚取更多的收入。

But this wage penalty does not appear to be gender specific. A paternity quota of parental leave was introduced by the Norwegian government in 1993, and a study found a similar negative effect on the earnings of stay-at-home fathers.

但这种工资惩罚似乎并不是针对性别的。挪威政府于1993年让爸爸们也享受到了“育儿假”福利，然后一项研究发现，对父亲的收入也有类似的负面影响。

The bottom line is, if you take time out to have a family there will be a drop in earnings.

最重要的是，如果你抽出时间来组建家庭，那么收入就会下降。

When to start?

那什么时候生孩子最好

The scientific data is clear. The "right" age to have a child according to your biological clock is under 35 for women and under 40 for men.

科学数据很清楚。从生物学角度来说，生育孩子的“正确”年龄：女性不到35岁，男性不到40岁。

More than 75 percent of young people underestimate the impact of age on male and female fertility – yet only 27 percent of doctors discuss this with patients aged 18-34 years who wish to delay childbearing for social reasons.

超过75%的年轻人低估了年龄对男性和女性生育能力的影响——同时，只有27%的医生会与18—34岁的患者讨论这一问题。

There needs to be a greater awareness about the risks of delaying family planning, and family doctors should play a more proactive role in this.

为了让大多数适龄男女意识到延迟生育的风险，家庭医生们应该发挥更积极的作用。

So, ultimately, if you want to have a child, the right age may be sooner than you thought.

所以，如果你真想要一个孩子，宜早不宜迟。