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Surely all women must have a maternal instinct or the human race would die out. We are mammals, and all other female mammals seem to have one. Maternal instincts and breasts—surely that’s what it means to be a mammal. Some women don’t seem very interested in having babies but that can’t be normal—can it?
Firstly, let’s look at this term ‘instinct’. The 1961 edited volume ‘Instinct’ laid down some defining guidelines. To qualify as an instinct, the behavior should be automatic, irresistible, triggered by something in the environment, occur at some particular time during development, require no training, be unmodifiable and occur in all individuals of a species. The problem with these criteria is that even the universal instinct to eat when hungry doesn’t fit well. Compared to other animals—my cat for example—it’s not automatic and irresistible. I have to physically restrain my cat from drinking my daughter’s milk and I don’t think he could ever decide to go on a diet.
So few (if any) human behaviors qualified as ‘instincts’ that psychologists replaced the term with ‘drives’. The idea is that we have a set of innate drives that pushes our behavior in preset directions. Drives are not unmodifiable or even irresistible, like instincts—but they are innate. They are not learned—and (with occasional exceptions) they are universal. We all have them. Drives motivate us to do stuff so that we don’t just sit around and die. I’m sure we’ve all experienced the inner battle that ensues when you need to do something but just have no motivation. Some drives clearly help us to survive and it is not difficult to see how they would have evolved. A rat treated so that it loses the normal dopamine response in the brain that triggers motivation will sit in front of a pile of food and starve because it just no longer ‘wants’ to eat. They don’t tend to want sex much either. An animal that doesn’t want food or sex is definitely in an evolutionary cul-de-sac.
But what about an animal that doesn’t want to have babies? As long as they keep having sex – babies will come along. They don’t need to be interested until then. And for most of human history this was our situation. Women didn’t have to want a baby as long as they wanted sex (or sadly, as long as they had sex whether they wanted it or not). In general, people have sex just because they want to. That’s the proximate reason. The ultimate reason is so that people will have children and the human race will keep running. But securing the future of the human race is not usually the motivation for individuals to have sex. It doesn’t’ have to be—it’s a natural consequence of the proximate motivation.
Although there are ancient records of family planning methods ranging from the spermicidal half-lemon cap to herbally induced abortions it is only in the last century that contraception has become widespread and reliable. A woman using contraception now has to stop and think: do I want to have a baby or not? For many women this is similar to wondering whether you might like to see the film ‘Motherhood’. You’ve read about it and it could be interesting and entertaining but you’re not sure if it’s really your kind of thing—you could be wasting time and money better spent saving for that trip around the world. A lot of people seemed to like it but you know one or two who really didn’t and some of those who did have so little in common with you their opinion hardly counts. And your partner doesn’t seem too keen right now—he’d rather go bowling. Would you go on your own? In the end—it’s just a movie and all that’s at risk is a few pounds and a few hours that you’ll never get back. But what if there was more at stake? What if you had to live that movie every day for the next 18 years (at least)? Who would buy a ticket for that level of commitment?
The press is awash with warnings about delaying motherhood and the short-sighted selfishness of career-hungry women who suddenly realize that ‘Motherhood’ is in its final week of release and it’s now or never. The implication is that either these women have been suppressing their maternal drive in pursuit of other rewards and pleasures or they never had any maternal drive and just want to tick off ‘having a baby’ from their lifetime achievement list. It’s as if there are two kinds of women—the kind that are born wanting a baby and the other kind that might or might not decide to have a baby depending on whether it is on their ‘to do’ list. Many women find the decision to have a baby agonizing because they think they should just know, intuitively, whether they really want one or not. If they don’t feel really driven then maybe they are not cut out for motherhood.
Talking to women of all ages soon reveals a wide range of interest levels when it comes to having a baby. Some recall wanting a baby when they themselves were still children. Others felt it from puberty. For many, the desire is not very strong as a young adult but increases into their 30s and 40s. And some are just not interested. For many of the women who have children later it’s not that they have put off something they had wanted for a long time or that they are having a child just because the baby shop is closing—the urge to have a child is just not there earlier.
Rather than a single, all-purpose maternal instinct women may be predisposed to a range of strategies and responses to circumstances. As a result, a mother’s behavior depends not only on her situation when she becomes a mother, but also her life experience and that of her own mother. There are situations and experiences which can prime girls’ maternal drives. Contact with babies can alter hormone levels in both sexes but especially in girls. Cues about safety, social and material support all contribute toward turning the maternal drive up or down (and not necessarily as you might expect: many animals in poor conditions reproduce fast and young).
The most important maternal behavior comes after the baby is born. Drives are not necessarily connected to pleasures. A mother can love and enjoy her child whether or not it was planned—and vice versa. This is what makes the decision such an agonizing one for women who are not gripped by the urge but not immune from it either.
