Three months after the birth of her first child in November 1994, Madam Siti Hawa Shaini found herself pregnant again.
The 52-year-old recalls: "I was surprised and worried about whether I could cope."
After two months of maternity leave, she had returned to work as a teacher and, earlier that year, had also started a part-time five-year degree course in mathematics at UniSIM.
In October 1995, she delivered her second girl, 11 months after she had her first child. She left both children in the care of a babysitter during the day and took them home in the evening.
She says with a laugh: "I don't know how I eventually managed to get my degree, without taking no-pay leave. Luckily, my daughters were not difficult. After six months, they were sleeping through the night."
Her husband, Mr Aminuddin Noor, 53, a senior customer service officer, helped her with them and also took care of the cooking and housework.
She adds that she was able to be intimate with him about six weeks after giving birth because her first child was "quite easy" and her husband was "very supportive", so she did not feel "too tired".
Looking back, she is glad she had them so close together because the girls, now aged 20 and 19, are "very close to each other".
Madam Siti, who was nominated for Jamiyah's exemplary mother award last year, has a third daughter, now aged 17, a pair of 11-year-old twin boys and an adopted son, aged 16.
Anecdotal evidence suggests many women resume sex by six weeks after giving birth and, in theory, a woman may be able to conceive as early as 45 days after giving birth, says Dr Anita Kale, a consultant at National University Hospital (NUH) Women's Centre. Breastfeeding may delay the conception process, though it is not foolproof, she says.
But research shows an interval of under 18 months is associated with an increased risk of preterm birth and low birth weight among others. Maternal nutrients may also not be replenished sufficiently.
Short pregnancy intervals are associated with increased risk of uterine rupture in women attempting a natural birth after a Caesarean delivery.
In fact, the World Health Organisation recommends the gap between a live birth and the beginning of the following pregnancy be more than two years and less than five years.
Dr Chong Shang Chee, head at NUH Child Development Unit, says besides ensuring an adequate gap, it is more important to consider other factors which may affect the parents' ability to cope in closely spaced pregnancies.
Considerations include finances, time commitment (for instance, if they are working), the type of help they can get and how challenging the children are.
She says: "Children learn best through interaction, time and secure attachment with their parents and caregivers. If we are too busy or stressed, then we cannot devote sufficient time or channel our energies to helping them achieve their potential."
Mrs Gail Leong, 40, quit her teaching job in December 2009 when she found out she was pregnant with her second child. Her first daughter was then only seven months old and being taken care of by her mother in the day.
Says Mrs Leong:"I wanted to spend more time with the older one and to prepare for the baby's arrival. I could afford to stop working because my husband and I were financially comfortable."
Her husband, Mr Leong Chun Keong, 41, is a teacher.
It turned out to be a good decision as her second child was more challenging than her first. Both were full-term babies, delivered naturally and born about 12 months apart.
Mrs Leong recalls: "The second one had eczema and couldn't sleep easily. The first six months were the worst because she would wake up every half hour to an hour at night, to suckle for comfort.
"I hardly slept. Even though I was not working, I had never felt so exhausted in my life."
Things got better after a couple of years when her daughter's eczema improved, adds Mrs Leong, who has since returned to full-time work as an executive officer in a charity organisation. Her daughters, now aged six and five, are in full-day childcare.
Ms Leung Sau Wai, 36, also contemplated quitting her job to be a stay-at-home mum after her second child, a son, was born 14 months after her daughter. Both were full-term babies delivered naturally.
But she decided against it and left her older daughter with her mother-in-law and the younger one with her mother.
She says: "My husband and I felt we'd be more comfortable with a dual income. Both of us had been working for only two to three years then. Also, I felt I would be a better mum if I worked." Her husband, Mr Teo Wee Keong, 38, is an engineer.
With two kids close in age, it meant that diaper, milk powder and future childcare and medical expenses would be doubled.
Despite these challenges, parents with closely spaced children say these are outweighed by the benefits.
Ms Lim Hai Yen, 44, a freelance writer, who has three children, aged 14, 11 and 10, says that even though all three are close, the two younger ones, who were born 15 months apart, are especially close to each other.
And because she had wanted to stop having children by age 35, it was good that the two younger ones came quickly so that she could get "the tiring diaper-changing and breastfeeding phase over and done with".
Ms Leung adds that as her children, now seven and six, are only 14 months apart, they were comfortable with each other from the start.
She says: "The older one was the only child for just 14 months, so to her, it was normal to have a sibling around. The second one had no choice. So they learn to share and care for each other."
After the first three years, they were "so easy to handle".
Adds Ms Leung: "They have been able to play and enjoy the same activities together as they are at the same developmental stage. They read the same books, play the same toys, sing the same songs and do the same crafts. It's easier to plan family outings without waiting for years for the younger one to take part."
Dr Chong from NUH says that having a sibling who is at least three to four years older who can talk and play appropriately with his younger sibling can increase the language learning and emotional development of the younger one.
That said, she says there is no evidence that the second child in a closely spaced pregnancy will be developmentally disadvantaged, unless he is significantly neglected.
Ultimately, there is no ideal age gap between siblings, says sociologist Tan Ern Ser, a council member of the non-profit Families for Life.
He says: "What really matters is strong families, in which children are loved and nurtured, and where siblings are taught to be considerate, respectful and supportive of one another."
This article was first published on Feb 22, 2015.
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