I had a baby in my 40s. Part of my job is preparing my daughter for life without me.

I am a midlife mom.

With a little help from modern medicine and a few meridian-stimulating acupuncture sessions, I had my now 6-year-old daughter in my mid-40s, gaining entrée into the fastest-growing group of women having children later in life.

I would have made a terrible mother in my 20s or 30s. In my 20s, I couldn't imagine raising a child — I was too much like one myself. I had lots of big ideas and ambition but no idea how I was going to make it happen. In my 30s, as I built my career as a magazine editor and journalist, I focused on accruing experiences. I smoked "flavored tobacco" in a hookah bar in Amsterdam, watched the sunrise at Haleakala's summit in Maui, 10,000 feet above sea level, and crashed a party at a mogul's Hollywood mansion.

During those years I picked unstable partners, like the karaoke-loving musician from Colorado who ended up moving to Mexico and living in his car, or the man with bipolar disorder who collected the martial arts weapons of the ninjas — antique nunchucks — €”and practiced with them while I cowered in a corner.

Stymied by my lack of progress in my personal life, with the help of a good therapist I reevaluated my choices. By my 40s I felt satisfied with what I'd achieved in my career, was ready to settle down, and had met a man who was my close-to-perfect match. I felt grounded, with a strong, unshakable sense of self — a great entry point into marriage and motherhood. Only after I got married and saw what a great father my husband would be did I realize that I wanted to have a child with him. Finally, I was ready to be a mother.

Becoming a mother in midlife after years of being responsible only for myself was the greatest transformative experience of my life. I wasn't in the least bit prepared for it. Here's what I wish I'd known before I got pregnant.

1) I had to make new friends

Starting from scratch to build a new social structure was hard, because my contemporaries had much older children. At first I felt very isolated and lonely. Although I signed my daughter up for music classes at our local Jewish community center when she was 3 months old, I found most of the moms there had toddlers and no interest in connecting with the mother of an infant. Also, I was paranoid that all the kids running around would step on my daughter or touch her and transmit germs.

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I would see all the other moms chatting and thought that they all looked so young yet seemed to handle motherhood effortlessly, as they diapered and fed their kids with aplomb while chatting. I found mothering a constant struggle — learning how to diaper my daughter without splattering her poo everywhere, figuring out how to collapse the stroller and get it into the car, swaddling her without her unwrapping it. Most of the time I felt like a failure.

I found my first mom friend a few months later, when I persuaded a man in the elevator of my building to give me his wife's number because he had a baby gurgling in the stroller who looked to be my daughter's age. Although we had a good rapport and enjoyed "mom conversation" (how to cut my daughter's fingernails, the best pediatrician, what to do about that rash), she moved away soon after we met.

I needed a sisterhood but had no idea where to find it. My best friend was married without children. The rest of my friends were still single, which is common when you get married later in life. They adored my daughter, but the Broadway shows, hot new restaurants, and pub crawls we used to enjoy together all had to take a back seat to my new lifestyle.

After overhearing someone talk about it, I joined Meetup.com when my daughter was 11 months old, and it was a game changer. I met a few moms in their late 30s and early 40s whom I felt comfortable with. One of them invited me to join her book club, and slowly I began to find my tribe.

2) Kids in midlife are draining

All new moms complain about being tired after having a baby. But being an older mom makes you even more exhausted. Though I used to stay up all hours, after becoming a mom the thought of staying up past 9 pm made me weary. I realized something I'd never thought of before — €”my prodigious energy was finite.

To refuel, I became addicted to energy drinks, and soon I was downing six to 10 cans a day. The burst of sugar gave me a short boost of energy, which would quickly dissipate, further sapping me of my stamina. It took months to wean myself off the stuff, and only after an "intervention" by my best friend.

My constant state of exhaustion caused me to snap at the slightest provocation. Soon after my daughter was born I called the phone company over a mistake I had found on the bill. "This is unacceptable," I cried to the rep, sobbing tears of frustration. "You can't do this to me." My husband, overhearing me, gently took the phone away. "I'm sorry, my wife just had a baby, and she's exhausted and worn down," he said. "We'll get back to you at another time."

I was not only out of sync with my emotions, I was also out of sync with my peers. When I attended my 25-year high school reunion I shared my baby pictures, while everyone else was sharing pictures of their kids' high school graduations.

I also had to deal with the increasing demands of my septuagenarian parents while parenting a baby. My dad was suffering from cognitive issues exacerbated by a broken hip, and my mom had high blood pressure. They needed a lot of attention and help. While I was glad that they could experience being grandparents to a young child again, I knew they — and I — would have had more energy, less anxiety, and more patience if we were younger. They recently moved closer to my sister, who just became an empty nester and has more time to devote to them.

3) I leaned out and then leaned back in

The author and her daughter. (Estelle Erasmus)

Before becoming a mom, I had never been interested in changing the world. Then I learned that corporate America only gives lip service to the idea of a mother finding life-work balance through flexibility from her employer. In our current archaic structure, the concept of the "perfect" worker does not reflect the realities of the modern family.

Passionate about this idea, I became involved in a now-defunct national organization called Mothers & More, which focused on advocacy for moms and building community via meetings and online events. I started speaking and writing about the role of mothers, and eventually became the president of the board of the organization.

I'm still interested in paving the way for women and mothers, mostly through my writing, so my daughter's generation can reap the rewards. With essays in Love Her Love Her Not: The Hillary Paradox, and What Do Mothers Need? I wrote about Hillary Clinton's new focus on her feminine side and the media's myths of motherhood. Through my vote in this upcoming election, I'm hoping to tip the balance of power. Because I'm older, it is very clear to me that unless I try to change the status quo, it won't be changed in time for my daughter to benefit from it.

4) I am very aware of my own mortality

After I'd been diagnosed with age-related infertility, it was hard being treated as imperfect, even though I was perfectly healthy. I felt like cattle being poked and prodded on a daily basis and undergoing invasive procedures. Finally, I was thrilled to get pregnant and give birth. But in a cruel twist of fate, I soon started getting the first symptoms of menopause — body changes, night sweats, and mood swings — as the hormones began to leave my body in droves. Young women don't have to deal with these kinds of life transitions stacked one on top of the other. But I had no choice.

Also, as an older mom, I'm aware of the cycles of life in a way that a younger mom couldn't possibly be. I think a younger mother imagines that she and her baby have all the time in the world. I, on the other hand, know the truth. And I do everything to prepare my daughter to live in that world.

Do I wish I'd had my daughter earlier? On the days when I'm fighting exhaustion, torn between my needs and hers, yes. But becoming a mom in midlife gives me the ability to parent her with perspective. I'm healthy, with supportive friends and a solid marriage. My goal is to teach her how to be resilient and emotionally intelligent and to help her make good choices for as long as I can — through the benefit of my hard-earned life's wisdom.

Estelle Erasmus is an award-winning journalist, writing coach, and former magazine editor in chief. She has been published on Salon, Newsweek, Yahoo, Brain, Child, and Your Teen. She writes the Practice of Parenting column for PsychologyToday.com and is a regular contributor to the Washington Post's On Parenting. Follow her on Twitter and Facebook.

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