On the road to Nigeria's northern state of Jigawa, you soon notice life becoming more rural after leaving the outskirts of Kano city.
Men on motor-bikes are gradually replaced by homes made of mud, and fields of corn and millet are being worked on by hand.
Attacks in Kano six months ago by the militant Islamist group, Boko Haram, have made the atmosphere here more insecure and quieter than usual. The security situation has affected some development work, too.
The neighbouring state of Jigawa is also poor, rural and mainly Muslim - but more peaceful.
Financial pledges to help get contraception to an extra 120m women in areas like northern Nigeria by the end of the decade will be announced at a big meeting in London on Wednesday 12 July.
It has been jointly organised by the Bill & Melinda Gates Foundation, and the UK government's Department for International Development (DfID).
Jigawa's is a traditional society. Often there's resistance to the idea of contraception: people fear it will lead to infertility.
A health worker in the villages of Jigawa, Aisha Ibrahim, said: "Like my colleagues, I go into women's homes at any time of day if we are called upon. We enter the compound at any hour if they need help with family planning or if they have other health needs."
The generator is whirring so that laboratory tests can continue at a small hospital in the village of Kiyawa.
And the family-planning logbook is being pored over by the DfID's north Nigeria health adviser. Susan Elden hails from Ohio but has also worked as a public-health specialist in the NHS in the north-east of England.
She told me: "We've had high demand for contraception here, but all we have at the moment in this primary health centre is oral contraceptives - that's it.
"So we're completely out of stock of the preferred method for women here, which is the contraceptive injection."
Injections are more popular because they last for several months, meaning women who live far away from the health centre have to travel less often. And if a woman needs to disguise using contraception from her husband, an injection is less obvious than a packet of pills.
Susan added: "There are a few reasons for this stock problem. Some of it is difficulties with getting stocks from the central medical stores.
"There's also an issue with training - the person that was previously doing the ordering has now left."
Habiba Dabi, a local nurse, said: "We need the injection and we suggest it to the patients because sometimes they forget to take the tablets."
Talk of "stock outs" like this one cropped up frequently in Nigeria, although I was also told that the hospital would definitely have fresh supplies before the next family-planning clinic.
In the wealthier south of the country there are rumours that some drugs are siphoned off into a thriving unofficial market.
In the north, there is much less awareness of contraception - and the problems arise because of a lack of experienced staff to forecast and order supplies.
'Not about religion'
British-funded aid programmes have already improved the provision of free contraceptives, and are helping to train 100 new community health workers in Jigawa.
A class of students was just down the corridor in the hospital. All of them were in neat white uniforms, the men wearing ties.
One of the trainees, Abas Omar, told me: "Our economic status isn't at a level where people can take care of the family they have. So we give them the basic information about family-planning services."
The link between developing family planning and helping Nigeria to be more prosperous and stable for all its residents resonates back in the capital Abuja with the government health minister, Dr Muhammad Ali Pate.
In a country that is far from straightforward, Dr Pate is regarded as a reformer who has improved some of the logistical problems with contraceptive supplies and boosted the provision of midwives.
He said: "This is not about religion. You can look at predominantly Muslim countries, like Bangladesh, which have done tremendously well with managing the fertility rate among their women.
"This is about access to services and the empowerment and role of women - not just in society, but also in their households.
"The system is not yet optimal in how it's functioning with the 'stock outs' sometimes occurring. And the level of financing isn't yet where it should be. We have to increase the funding for contraception.
"We have these challenges in our health system, and we are working hard to improve matters."
He added: "We're aiming to save a million lives over the next three years. We know which interventions will get us there. It's not as if this is something uncharted.
"And what is good value for the British pound, is good value also for the Nigerian naira."
Wednesday's summit shows that contraception remains a controversial subject, though.
Anti-abortion campaigners at the Society for the Protection of Unborn Children (Spuc) claim that the meeting will be used to help promote abortion.
A spokesman said: "Far from avoiding abortions, the Gates family-planning summit may increase the number. Increasing contraceptive prevalence may often increase abortion rates, contrary to expectations.
"Abortion and contraception are seen as part and parcel of family planning and so-called reproductive rights."